Corrigendum: The Complexities in Genotyping of Congenital Adrenal Hyperplasia: 21-Hydroxylase Deficiency.

[This corrects the article on p. 432 in vol. 10, PMID: 31333583.].

The Complexities in Genotyping of Congenital Adrenal Hyperplasia: 21-Hydroxylase Deficiency.

The deficiency of 21-hydroxylase due to CYP21A2 pathogenic variants is a rather frequent disease with serious consequences, going from a real mortality risk to infertility and to milder symptoms, nevertheless important for affecting the patients' self-esteem. In the most severe cases life-threatening adrenal salt wasting crises may occur. Significant morbidity including the possibility of mistaken gender determination, precocious puberty, infertility and growth arrest with consequent short stature may also affect these patients. In the less severe cases milder symptoms like hirsutism will likely affect the image of the self with strong psychological consequences. Its diagnosis is confirmed by 17OH-progesterone dosages exceeding the cut-off value of 10/15 ng/ml but genotyping is progressively assuming an essential role in the study of these patients particularly in confirming difficult cases, determining some aspects of the prognosis and allowing a correct genetic counseling. Genotyping is a difficult process due to the occurrence of both a gene and a highly homologous pseudo gene. However, new tools are opening new possibilities to this analysis and improving the chances of a correct diagnosis and better understanding of the underlying mechanisms of the disease. Beyond the 10 classic pathogenic variants usually searched for in most laboratories, a correct analysis of 21OH-deficiency cases implies completely sequencing of the entire gene and the determination of gene duplications. These are now recognized to occur frequently and can be responsible for some false positive cases. And finally, because gene conversions can include several pathogenic variants one cannot be certain of identifying that both alleles are affected without studying parental DNA samples. A complete genotype characterization should be considered essential in the preparation for pregnancy, even in the case of parents with milder forms of the disease, or even just carriers, since it has been reported that giving birth to progeny with the severe classic forms occurs with a much higher frequency than expected.

Erythropoietic protoporphyria: a family study and report of a novel mutation in the FECH gene.

Erythropoietic protoporphyria (EPP) is a rare inherited disorder of heme biosynthesis mostly caused by a deficient activity of the enzyme ferrochelatase (FECH), and consequent accumulation of protoporphyrin (PP) in various tissues. Clinical manifestations include a childhood onset, cutaneous photosensitivity and, sometimes, hepatobiliary disease. We report a 16-year-old male with EPP characterized by acute episodes of painful photosensitivity since early infancy, permanent changes in the photoexposed skin, microcytic anemia, thrombocytopenia, and mild hepatic dysfunction. His 18-year-old sister presented less acute symptoms with no chronic changes. Lesional biopsy disclosed perivascular deposition of PAS positive hyaline material. Rimington-Cripps test was positive and PP erythrocyte levels were >9,000 µg/L (N<1,600), but normal in their parents and younger brother. Genetic studies in both patients and their mother revealed heterozygosity for a novel mutation (c.1052delA) in FECH gene of both children, and heterozygosity for the hypomorphic allele IVS3-48T>C in all of them. This confirms the "pseudodominant" inheritance pattern usually observed, explained by the combined presence of a disabling FECH mutation and a common intronic polymorphism affecting the counterpart allele (IVS3-48T>C). Phenotypic heterogeneity for this genotype explains the divergent clinical presentation. This is the first description of a Portuguese family with EPP characterized at the molecular level.

Vascular Ehlers-Danlos syndrome: a case with fatal outcome.

A 13-year-old boy, born prematurely and hypotonic, from non-consanguineous healthy parents, was referred to our department because of easy bruising. A slightly extensible, thin and translucent skin, associated with dysmorphic facies, acrogeria, multiple ecchymoses, hypermobility of the small joints, dorsal kyphosis, genu valgum, flat feet, elongated upper limbs, and low muscle tone were all evident. A history of learning disability and bilateral inguinal hernia was present. Blood and imaging studies were unremarkable. A skin biopsy disclosed an unremarkable dermis; electron microscopy showed abnormalities in the diameter, contour, and shape of collagen fibrils/fibers. Genetic analysis revealed heterozygosity for a novel mutation in COL3A1 gene (c.3527G>A), confirming the diagnosis of vascular Ehlers-Danlos syndrome (VEDS). The patient died at 15 years of age because of aortic dissection. Vascular Ehlers-Danlos syndrome is a rare, life-threatening, autosomal dominant variant of EDS, resulting from mutations in COL3A1 gene. Affected individuals are prone to serious and potentially fatal complications, especially vascular, intestinal, and uterine ruptures. Delay in diagnosis is common, even when the clinical presentation is typical. Therefore, dermatologists should be familiar with VEDS features because the skin findings may be the first signs. Early diagnosis will improve management of visceral complications and allow early genetic counseling.

Novel deletion encompassing exons 5-12 of the UBE3A gene in a girl with Angelman syndrome.

Angelman syndrome (AS) is characterised by severe developmental delay, severe speech impairment, gait ataxia and/or limb tremor and a unique behavioural phenotype. The diagnosis of AS is based on a combination of clinical features and molecular genetic testing. Currently, molecular genetic testing (methylation analysis and UBE3A sequence analysis) identifies anomalies in about 90% of individuals. The aetiology of the remaining 10% is still unknown. We report a novel deletion encompassing the exons 5-12 of the UBE3A gene in a girl with AS, identified by MLPA (Multiplex Ligation-dependent Probe Amplification), which was not detected by the conventional diagnostic protocol. We propose that copy number analysis of the UBE3A gene should be considered in individuals whose clinical examination is strongly suggestive of AS, after more common mechanisms have been excluded.

Single-test parallel assessment of multiple genetic disorders.

We advocate a new paradigm for genetic diagnosis based on using customized array panels, each of which groups multiple genes and mutations associated with clinical profiles that are common to particular syndromic diseases. This parallel approach, based on a single-test multigene multiplexing strategy, compared with traditional sequential testing by gene-by-gene genetic analysis, drastically reduces the time and cost of diagnosis while maintaining accuracy and reliability. Faster diagnosis enables early decision-making to facilitate better patient management and outcomes at reduced costs to the healthcare system.

Platelet hyperactivation in maintained growth hormone-deficient childhood patients after therapy withdrawal as a putative earlier marker of increased cardiovascular risk.

GH deficiency (GHD) is associated with a higher risk of vascular disease, whose pathophysiological mechanisms remains not yet fully elucidated. This study aimed to assess the main cardiovascular risk indexes, plasma catecholamines content, and the platelet function in childhood-onset GHD patients. Some of the main clinical examinations related with cardiovascular risk, plasma catecholamines content, as well as platelet intracellular free calcium concentration ([Ca(2+)](i)), whole-blood aggregation, and morphology were evaluated in childhood-onset GHD patients treated with GH for a variable period and off GH therapy for at least 2 yr before entry into study and in sex-, age-, and body mass index-matched control groups. Among the patients, group 1 (GHD-1) has recovered GH levels after withdrawal, whereas group 2 (GHD-2) has remained GH deficient. Minor differences on the cardiovascular risk indexes were observed between the groups. Plasma catecholamine concentrations in the GHD groups did not statistically differ from the control group, but higher adrenaline content was observed in the GHD-2 group when compared with the GHD-1 one. Basal and thrombin-evoked [Ca(2+)](i) and platelet aggregation were identical between the GHD-1 group and the matched control. However, the GHD-2 group has increased thrombin-evoked [Ca(2+)](i) (297.0 +/- 15.7 Deltanmol/liter; P < 0.01), collagen, and ADP-induced platelet aggregation (33.3 +/- 4.3 and 12.5 +/- 2.1 Omega, respectively; P < 0.05) vs. the control-2 group (Delta[Ca(2+)](i): 102.1 +/- 13.6 Deltanmol/liter; aggregation: 19.6 +/- 2.9 and 6.2 +/- 0.8 Omega). The platelet hyperreactivity state in the GHD-2 was reinforced by morphologic studies of electron microscopy. In conclusion, there were minor differences between the GHD-1 group and the controls, which might be due to the recovery of GH levels after therapy withdrawal. However, the maintained GHD group, despite minor cardiovascular risk index differences, has increased [Ca(2+)](i) and aggregation, which could indicate a hyperactivation state that might be viewed as an earlier marker of cardiovascular disturbances.

Isosorbide-5-mononitrate treatment prevents cyclosporin A-induced platelet hyperactivation and the underlying nitric oxide-cyclic guanosine-3',5'-monophosphate disturbances.

INTRODUCTION: The clinical use of cyclosporin A (CsA) is commonly associated with the development of hypertension and increased risk of thromboembolic events. Decreased endothelium-dependent relaxation and increased platelet activation seems to be involved on those side effects, but the underlying mechanisms are not yet elucidated. The present study aimed to evaluate the CsA effect on the platelet NO-cyclic guanosine-3',5'-monophosphate (cGMP) pathway and the putative benefits of concomitant isosorbide-5-mononitrate (IS-5-MN) administration on CsA-induced hypertension and on platelet hyperactivation. MATERIALS AND METHODS: Blood pressures, platelet NO synthase activity and cGMP content, intracellular free calcium concentration ([Ca2+]i) and whole blood platelet aggregation were assessed in three rat groups orally treated, during 7 weeks, with the following diets: orange juice (control group), 5 mg/kg/day of CsA (CsA group) and 150 mg/kg/day, b.i.d., of IS-5-MN for 2 weeks and IS-5-MN plus 5 mg/kg/day of CsA for 7 weeks (IS-5-MN+CsA group). RESULTS: IS-5-MN treatment has prevented hypertension development obtained in the solely CsA-treated rats. CsA treatment has inhibited NOS activity, which was reverted by the concomitant IS-5-MN and CsA administration. On the contrary, platelets from CsA-treated rats had cGMP content increased when compared with the control rats. The variation obtained when ISMN was present was less predominant. Therefore, the organic nitrate treatment has prevented platelet hyperactivation, namely, by decreasing thrombin-evoked [Ca2+]i and collagen-evoked platelet aggregation, when compared with the solely CsA-treated group. The preventive effect of IS-5-MN was reinforced by electron microscopy studies of platelet activation. CONCLUSIONS: By increasing [Ca2+]i and aggregation, CsA induces platelet hyperactivation and simultaneously increases cGMP content, which might represent a compensatory inhibitory mechanism. The concomitant IS-5-MN treatment prevents the above-mentioned platelet hyperreactivity and tends to normalize the NO-cGMP pathway as well as the development of hypertension.